Hi,
Can someone explain how the newly added Projected Australian GDA2020 GCS works in Microstation CE U11?
We have the old GDA94 GCS group, a new GDA94-7P (7 Parameter Transformation to 2020), GDA94/GSB (GDA94 to 2020 using Grid Shift files) and a plain GDA2020 GCS group. If I reproject the data from the old GDA94 to the GDA-7P or GDA95/GSB GCS settings my data moves as expected, however nothing happens if I go from the old GDA94 to the new GDA2020.
How is this supposed to work?
Regards,
Mark
Mark,
In order to migrate from GDA94 to GDA2020 you must first change or correct the Geographic Coordinate System from the GDA94 system, to the equivalent based on GDA94/GSB -- without reprojecting. This is a Correction from a coordinate system that used to be based on WGS84 to something that is not anymore (GDA94 used to be considered coincident to WGS84. Now it is GDA2020 that is considered coincident to WGS84 but we cannot change the definition of GDA94 after its existence).
Once that is done you can reproject to the GDA2020-based Geographic Coordinate System.
So your process will be a two-step process; 1. Correct the Geographic Coordinate System, do not reproject the data. 2. Reproject the data
Answer Verified By: Mark Shamoun
Excellent, that makes sense.
Thanks Dan!
OpenRoads Designer 2023 | Microstation 2023.2 | ProjectWise 2023
Hi Dan
Can you provide more information on how to do the reprojection part of the 2 steps? Changing the geographic coordinate system is obviously what the screenshot shows above, but having first selected 'do not reproject the data', what do you have to do to reproject the data?
-W
Hello Wendy,
The last step to reproject the data occurs when you select the system with GDA2020 details and the dialog presents you with the same two options - Correcting the data, or Reprojecting the data. You would select the 2nd choice, or "Reproject the data to the new Geographic Coordinate System".
The process actually considers three coordinate systems, and two steps:
1. The original WGS84 coordinate system
2. The intermediate GDA94 coordinate system, to correct the system
3. The final GDA94/GDA2020 coordinate system (this is the step to select "Reproject the data...")
Of course!
Thx
Hi Dan WestonI had to reproject a model from GDA94 to GDA2020 and your approach seemed to work, however since then, my reference display has been problematic. All references appear to be linked correctly and they do display in the 3D view, however nothing is showing in the default view. I have noticed that the X- and Y-offset of the references now shows a value of "-nan(ind)". Have you by any chance experienced the same issue or have any suggestions on how we can resolve this?Regards,